Lower Carbon Monoxide Emissions Research Articles

Energy and exergy analysis of a SI engine fueled with anisole and isobutyl acetate with super-premium gasoline

The rising demand for fossil fuels is rapidly depleting the limited sources of crude oil, leading to harmful emissions upon combustion. Consequently, developing sustainable and environment-friendly alternatives to fossil fuels has become imperative to reduce dependence on them and decrease harmful emissions. In this study, the performance of different blends prepared by mixing biofuels with super-premium gasoline (SPG) in a spark-ignition (SI) engine at different speeds is investigated through energy and exergy analysis. Three biofuels, namely ethanol, anisole, and isobutyl acetate, are considered, and these biofuels are blended with the base SPG in volumes ranging from 10% to 30%. Letters G, E, A, and IBA are used to denote SPG, ethanol, anisole, and isobutyl acetate, respectively. Experiments were conducted on a three-cylinder, four-stroke SI engine with varying speeds. The results of different anisole-SPG and isobutyl acetate-SPG blends are compared with SPG and ethanol-SPG blends. The results of the energy and exergy analysis reveal that the maximum brake thermal efficiency (BTE) and exergy efficiency are achieved when the engine runs at 2500 rpm for SPG and different blends. Furthermore, the engine emissions of carbon monoxide (CO) are found to be lowest at this engine speed. It is also investigated that the maximum BTE and exergy efficiency are obtained for AG10 and IBAG10 blends. The maximum BTE of AG10 and IBAG10 are 31.23% and 30.82%, respectively, while the maximum exergy efficiency of AG10 and IBAG10 are 24.37% and 23.82%. At 2500 rpm, the blends AG10 and IBAG10 showed a slight reduction in BTE by 1.72% and 3.02%, respectively, compared to SPG. At the same time, the exergy efficiency of the AG10 and IBAG10 blends is reduced by 1.5% and 3.72%, respectively. On the other hand, the IBAG30 blend showed 7% lower emissions of CO and NOx compared to SPG. Among all the blends, EG30 showed the lowest reduction of HC emissions by 14% compared to SPG. Additionally, the sustainability index values decreased by 0.47% and 1.19% for AG10 and IBAG10, respectively, compared to SPG at 2500 rpm.

Numerical and experimental analyses for performance and emissions assessment of a four-stroke engine powered by oleic acid methyl ester biofuel made from waste frying oil

<p style="text-align:justify"><span style="font-size:11pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="font-size:12.0pt"><span style="line-height:150%"><span style="font-family:"Times New Roman",serif">Recently, several earlier works conducted research works dedicated to replacing fossil-based fuels with environmentally friendly ones. The goal of the research is to construct a multivariate linear regression model for the attributes of a four-cylinder diesel engine fueled by biodiesel. In this context, the goal of the research is to structure a multiple linear regression example for characterizing a four-cylinder engine fueled by biodiesel. In fact, experimental research was conducted on an agricultural tractor equipped with a 4-cylinder direct-injection diesel engine. The biodiesel is made from waste frying oil without blending referred to as the oleic acid methyl ester (OAME) biofuel. The biodiesel was extracted through a chemical transesterification reaction. The four-stroke engine is tested for both pure OAME biofuel and conventional diesel. One-dimensional numerical simulations were conducted. A strong correlation between numerical and experimental data was observed, validating the numerical model. Using the engine model, in-cylinder pressure, heat release rate, in-cylinder temperature, and emissions including Carbon monoxide (CO), nitrogen oxides (NO<sub>x</sub>), and Carbon dioxide (CO<sub>2</sub>) were recorded across a broad range of engine operating speeds. Additionally, brake-specific fuel consumption (BSFC) and brake power were numerically calculated and compared to experimental data. The results showed that usage of the OAME as a biofuel could be a promising solution that enables similar performances with lower CO emissions compared to petroleum diesel particularly at low engine speeds.</span></span></span></span></span></span></p>

Investigation of performance and emission characteristics using ethanol-blended gasoline fuel as a flex-fuel in two-wheeler vehicle mounted on a chassis dynamometer

Abstract This study investigated the performance and emissions of flex fuels in a 110-cc BS6-compliant fuel-injected two-wheeler without ethanol adaptation adjustments. The tests were carried out under controlled conditions on a chassis dynamometer at 1000, 2000 and 3000 r.p.m. using ethanol blends from 10% ethanol (E10) to 85% ethanol (E85). Parameters examined included brake power (BP) output, brake-specific fuel consumption (BSFC), peak in-cylinder pressure and exhaust temperature. Emissions, including carbon monoxide (CO), hydrocarbons (HC), nitrogen oxide (NOx) and unregulated emissions, were also assessed. As the percentages of the ethanol blend increased from E10 to E85, there was a noticeable improvement in power output. At 1000 r.p.m., the BP ranged from 2.4 to 4.6 kW for different blends. The BSFC and the peak in-cylinder pressure followed a similar pattern, indicating enhanced performance and fuel efficiency with higher ethanol concentrations. Interestingly, using E85 at 1000 r.p.m. resulted in a significant 41.08% reduction in exhaust temperature compared with E10, although this difference decreased with higher blend percentages. Furthermore, replacing E10 with E85 at 1000 r.p.m. reduced CO and HC emissions by 9.17% and 38.34%, respectively. In contrast, NOx emissions increased at all r.p.m. levels with higher-ethanol blends, peaking at a 415 parts per million increase at 3000 r.p.m. However, unregulated emissions decreased significantly with increased r.p.m. and ethanol content. In summary, the use of flex-fuel blends in a two-wheeler resulted in a modest increase in BP output, improved fuel efficiency and lower CO and HC emissions. These findings are vital for optimizing ethanol blend utilization in two-wheeler engines under low-load conditions, considering both performance and environmental aspects.

Comparative Experimental Assessment of Pollutant Emission Behavior in Combustion of Untreated and Thermally Treated Solid Biofuels from Spruce Chips and Rapeseed Straw

Biomass energy for heating is going to be part of the spectrum of renewable energy sources. However, biomass combustion produces emissions of various pollutants with negative effects at both local and global scales. To reduce some of the locally important pollutant load, thermally treated biomass fuels may offer a partial solution. In this study, two biomass feedstocks, i.e., spruce chips and rapeseed straw, were thermally treated at 300 °C to produce biochars. Subsequently, both original materials and biochars were burned in a 25 kW retort combustion device. In both cases, the biochar showed lower emissions of carbon monoxide and nitrogen oxides, usually almost across the whole range of tested combustion conditions. In total, for the emission production per unit of net calorific value, the spruce biochar showed reductions in CO and NOx productions of 10.8% and 14.5%, respectively. More importantly, in rapeseed straw biochar, the difference was more pronounced. The total production was reduced by 28% and 42%, again in CO and NOx emissions, respectively.

Stable lean co-combustion of ammonia/methane with air in a porous burner

Ammonia is being considered as a promising zero carbon fuel due to its unique properties, while its combustion still poses challenges in term of instability and higher nitrogen oxides (NOx) emissions. In this study, the co-combustion stability of ammonia/methane with air under lean burn condition is experimentally investigated using a silicon carbide (SiC) ceramic foam burner with a two-layer structure stabilizing the flame. The influences of different operating parameters (methane fraction ω, equivalence ratio φ, and flow velocity V) on the co-combustion flame temperature and emissions are analyzed. The results indicate that the lean stable co-combustion of ammonia/methane with air can be achieved in two-layer ceramic foam burner, with its lower limit extending to φ = 0.5, even for the pure ammonia at specific operating conditions. Notably, the nitric oxide (NO) emissions decrease significantly as the equivalence ratio increases, particularly with a rise in methane fraction. The reduction can reach as low as 843 ppm with φ increasing to 0.9, further reducing to an ultra-low level of less than 150 ppm at φ = 1.3, significantly lower than those of traditional free flame burners. Carbon monoxide (CO) emissions remain at ultra-low levels, indicating the excellent co-combustion efficiency of ammonia/methane-air in the porous burner. An optimal co-combustion region with lower NO and CO emissions were conclusively identified. These findings demonstrate the effectiveness of porous media combustion in improving the co-combustion stability of ammonia/methane and reducing NO emissions, thereby helping to develop the porous burners of ammonia-based fuel and promoting its clean utilization for realizing carbon neutrality.

Enhancing biodiesel stability and performance: synthesis and extraction of macauba biodiesel for sustainable engine applications

The demand for sustainable fuels has driven research on biodiesel blends’ combustion characteristics and emissions. The study evaluates the performance of macauba and soybean biodiesel blends by analyzing torque, power, and fuel consumption indicators. The effects of leaf extract additives on engine performance are also assessed. Comparing macauba and soybean blends show similar load, brake power, and engine speed trends on response variables. However, slight variations in coefficients and significance levels indicate unique combustion and emission profiles for each blend. Understanding these distinctions is crucial for optimizing engine performance and emission control strategies. Parameters analyzed include brake-specific fuel consumption (BSFC), brake thermal efficiency (BTE), exhaust gas temperature (EGT), carbon monoxide (CO) emissions, hydrocarbon (HC) emissions, oxides of nitrogen (NOx) emissions, smoke opacity, cylinder pressure, heat release rate, and ignition delay. Blends 80% Soy Methyl and 20% Macauba Methyl Biodiesel (BSM20) demonstrates 5–10% superior fuel efficiency, 8–12% higher energy conversion capability, 3–5% lower exhaust temperatures, 10–15% reduced emissions, and 5–8% enhanced efficiency versus other blends and Diesel. It also shows 10–20% lower hydrocarbon and CO emissions, 15–25% reduced NOx, 20–30% lower particulate matter, and more efficient energy release during combustion. Optimizing heat release rate and ignition delay is crucial; BSM20 shows a 10–15% shorter ignition delay. Understanding blend distinctions is key for optimizing performance and emissions. BSM20 blend demonstrates superior fuel efficiency, energy conversion capability, lower exhaust gas temperatures, reduced emissions, and enhanced engine efficiency compared to other blends and Diesel. It also shows lower hydrocarbon, CO, and NOx emissions, reduced particulate matter emissions, and more efficient energy release during combustion. Optimizing heat release rate and ignition delay is crucial for cleaner combustion and improved engine performance.

Experimental and cfd analysis of the influence of fuel injection timing on the behavior of a gasohol-based gdi engine

ABSTRACT This work examines the impact of FIT (Fuel Injection Timing) on engine’s performance of an automotive, Gasoline Direct Injection (GDI) engine using Gasohol (85% Gasoline + 15% Ethanol by mass) as fuel. The start of FIT was experimentally varied from −280 CAD (Crank Angle Degrees) to −330 CAD at 10 CAD intervals by using an open ECU. Experiments were performed at variable power outputs (such as 5, 8, 10, 13, 16, 18 and 21 kW) at a constant speed of 2500 rpm. CFD simulations were carried out for the above said conditions to understand engine’s behavior. Considering the conventional start of injection, advancing the FIT showed improvement the BTE (brake thermal efficiency) up to −320 CAD BTDC. The maximum BTE was observed as 31.8% at the engine power output of 21 kW (whereas it was 28.6% at −300°CAD). CFD results confirmed the improvement in the air-fuel mixing rate and swirl motion. With the use of advanced FITs, the emissions of carbon monoxide (CO) and hydrocarbons (HC) were decreased. The CFD emission results for CO and HC showed good agreement with the experimental findings. With the advanced FITs, NOx emissions showed an increase at all loads. The in cylinder pressure was observed to be higher with advanced FITs. Modeling results are very well supported with experimental pressures. It is concluded that advancing the fuel injection timing might improve the performance and lower HC and CO emissions of a Gasohol-based GDI engine. The optimized injection timing of −320 CAD could be recommended for the aforementioned engine’s greatest performance.

Influence of the Use of EtG Synthetic Fuel in Spark-Ignition Engines on Vehicle Fuel Consumption and Pollutant Emissions

This article presents the properties of EtG synthetic fuel (Ethanol to Gasoline) as a substitute for fuels in an installation using ethanol from food waste as a raw material. The results of this research on the process of supplying the engine with EtG fuel are presented, in which the operational suitability of this fuel was verified, including environmental requirements. The results of pollutant emission tests from vehicles with spark-ignition engines in dynamic driving conditions in the New European Driving Cycle (NEDC) type approval tests and the World Harmonized Test Cycle (WLTC) test, both on a “cold” and “hot engine”, are presented. It was found that EtG fuel is characterized by lower emissions of carbon monoxide, nitrogen oxides, and methane, and higher emissions of non-methane hydrocarbons compared to E10 commercial gasoline, while the specific distance emission of carbon dioxide for both fuels was very similar.

CFD analysis of combustion and emission characteristics of biodiesel under conventional and late-injection based premixed combustion conditions

The simultaneous reduction in NOx and smoke emissions can be achieved with biodiesel under a late-injection based low temperature combustion (LTC) strategy. However, this occurs at the expense of a substantial increase in unburned hydrocarbon (HC) and carbon monoxide (CO) emissions. It is worthwhile to understand the reasons behind the formation of these emissions, emphasizing comparison with conventional combustion, which is known to result in significantly low HC and CO emission levels, particularly with oxygenated biodiesel fuel. The present investigation attempts to examine the same with 3D CFD simulation. Experimental data were obtained from a light-duty diesel engine using biodiesel from non-edible Karanja oil. The unmodified engine with OEM low-pressure mechanical fuel injection system was utilized for conventional combustion operation. It is replaced with a modified common rail injection system for a late-injection-based LTC mode of operation. By combining retarded high-pressure injection with EGR, sufficient premixing was sustained to enable late injection-based premixed combustion (LI LTC). The combustion simulation was performed using CONVERGE CFD tool, utilizing a two-component surrogate of methyl butanoate (MB) and n-dodecane to represent biodiesel. A reduced chemical kinetic mechanism, developed and validated in an earlier investigation on biodiesel combustion, was utilized in the current study. The mechanism was solved using the SAGE Detailed CHEMKIN solver in CONVERGE. Validation was conducted at two engine operating conditions defining low and high loads for both combustion modes. The cylinder pressure and heat release rates were predicted with a maximum error of 1.5 and 13%, respectively. The validated CFD tool was employed to compare and analyze the equivalence ratio, in-cylinder gas temperatures, and HC and CO contours between conventional and LI LTC modes. Under LTC mode, the cylinder pressure and heat release rates were predicted with a maximum error of 10 and 15%, respectively. The comparison revealed fuel-rich regions concentrated near the bowl in conventional combustion, while the fuel was spread throughout the combustion chamber in LI LTC mode with over-rich and over-lean regions near the cylinder wall. The cylinder temperature is significantly higher for conventional combustion than LI LTC mode. The O and OH radical concentrations are higher for conventional combustion, corroborating with lower CO emissions, as they aid in CO oxidation. Fuel-rich regions contribute to increased CO emissions, whereas over-lean regions at a low-temperature result in high HC emissions, exhibited by the emission contours. Possible countermeasures to reduce high HC and CO emissions in LI LTC mode include maintaining higher coolant temperatures to enable HC and CO oxidation in the near-wall regions and fuel injection system modification to alter the air–fuel mixing.

Impact of Improved Cookstoves on the Level of Household Exposure to CO and PM<sub>2.5</sub> in Sub-Saharan Cities: The Case of the City of Ouagadougou

Air pollution is one of the major global threats to human health. In Burkina Faso, more than 80% of the population uses solid fuels as the main source of cooking energy. This paper reports a comparative study on the exposure of household to the carbon monoxide (CO) and particulate matter (PM2.5) emitted by improved cookstoves (ICS) or traditional cookstoves (TCS). A cross-sectional study was conducted in the city of Ouagadougou for 4 months during the rainy season (July to October) in households with an outdoor kitchen. The investigation involved 92 households where air pollutants, such as PM2.5 and CO were measured with Indoor Air Pollution Meters (IAP meter). These measurements were focused on the concentration levels of the pollutants during cooking. The results of this study show high levels of PM2.5 and CO for all type of stoves. Wood stoves led to higher PM2.5 and lower CO emissions than charcoal stoves. ICS reduce emissions of indoor air pollutants compared to TCS. This reduction raised up to 82% for PM2.5 and 37% for CO. The analysis of the data measured with the student test (t-test) shows that there is a statistically significant difference between the average values of the concentrations of the pollutants emitted with the TCS compared to ICS, except for CO emissions measured on multi-pot sizes cookstoves (MM). This study shows that the concentrations of indoor air pollutants are very high regardless of the type of cookstoves used. The CO exposure obtained varies from 119.10 to 362.72 μg/m3 for 15-minute and 10.83 - 55.11 μg/m3 for 1-hour exposure. The exposure in PM2.5 varies from 4762 to 16,257 μg/m3 for 15-minute and 106.63 to 1597 μg/m3 for 1-hour of exposure. It was noted that the CO exposure levels obtained over 15-minute of exposure are 1.36 to 4.15 times higher than the WHO recommendation and 1.8 times higher for an exposure time of one hour. This means that women in charge of cooking have a high risk of exposure to air pollutants.

Effects of Changing Drive Control Method of Idling Wood Size Reduction Machines on Fuel Consumption and Exhaust Emissions

Operating conditions often fluctuate during processing of branches and sawmill offcuts using low-power wood size reduction machines (WSRMs), mainly due to changes in wood supply frequency. This results in relatively high proportions of idling time. Fuel consumption and associated exhaust emissions of WSRMs with combustion engines can be reduced by using innovative drive unit control systems during idling. The objective of the research was to determine the effects of two speed control systems on the fuel consumption and exhaust emissions of a WSRM with a two-cylinder cutting mechanisms driven by a small 9.5 kW spark ignition engine. Speed control system A (commercially available) had a substantially higher rotational speed than system B (an innovative, adaptive solution subject to patent application No. P433586). Pine (Pinus sylvestris L.) wood sawmill offcuts (average cross-sectional area, length and water content: 25×40 mm, 3000 mm and ca. 12, respectively) were used in system tests at a feed rate of ca. 5 pieces min-1. Material of this size is typically processed by such machines. Operating conditions were monitored by recording the rotational speed and torque. Emissions of harmful exhaust compounds–carbon monoxide (CO), carbon dioxide (CO2), hydrocarbons (HC), and nitrogen oxides (NOx) – were recorded using a portable emission measurement system. Fuel consumption values were also calculated from the data. The following effects were observed: application of innovative system B resulted in 33% lower fuel consumption, as well as 30%, 37% and 33% lower CO, CO2 and NOx emissions, respectively, than system A, but at the same time 290% higher HC emissions were registered. In operating conditions with higher proportions of idling time, solution B provides even higher reductions in fuel consumption and exhaust emissions.

Biomass Stove with Low Carbon Monoxide Emission Fueled by Solid Fuel Coffee-Husk Biopellet

In this study, coffee husk was used as the primary material to produce biopellets, with a mixture of tapioca flour and molasses as a binder. The concentration of each binder used was 10, 15, and 20%. The addition of tapioca flour and molasses at different concentrations increased the biopellets density, ash content, and fixed carbon content, and reduced moisture content and volatile matter content. The best formulation was obtained by adding 10% tapioca flour; it had a biopellet density of 610 kg/m3, an ash content of 3.03%, a moisture content of 8.03%, a volatile matter content of 81.79%, a fixed carbon content of 15.18%, a calorific value of 17.55 MJ/kg, a water-boiling time of 10 min, a fuel consumption rate of 0.008 kg/min, and a thermal efficiency of 33.15%. The design results were obtained using the distance from (diameter = 26.5 cm and height = 37 cm) the stove to the outside of the furnaces (this amounts to 8 cm, which can minimize the furnace, causing heat to generate from burning). The speed of the blowers can be adjusted by users using a dimmer. The results obtained from the stove’s performance showed the average thermal efficiency of the furnace, which with an average of 3.25 ppm.

THC and CO Emissions from Diesel Engines Using Biodiesel Produced from Residual Frying Oil by Non-Thermal Plasma Technology

Research aimed at finding alternative fuels to replace petroleum diesel (petrodiesel) used in controlled combustion engines (CCEs) has identified biodiesel as one of the main candidates, due to its sustainability and potential for use in energy matrices. In this study, the gas emissions from a diesel CCE were investigated, with a focus on total hydrocarbons (THC) and carbon monoxide (CO). Biodiesel (B100) samples derived from the transesterification of frying oil, produced applying conventional chemical catalysis (CC) or non-thermal plasma (NTP) technology, were tested as alternative fuels. Three engine rotation speeds were investigated (900, 1500, and 2500 rpm) and biodiesel samples obtained from the residual frying oil were compared with conventional road diesel (S-500) without biodiesel added, acquired from a gas station. Blends were also prepared with S-500 and B100 obtained applying NTP for 15 or 30 min, in mixes containing 2, 12, 20, and 50% of biodiesel. These blends showed reductions in THC and CO emissions of 62% and 80%, respectively, compared with the emissions for 100% S-500. Thus, biodiesel produced from frying oil offers low emissions of CO and THC, highlighting the potential for reductions using biodiesel produced applying the NTP technology.

Towards fossil-free fuels in sustainable powertrain; alcohol-fueled low-temperature combustion (LTC)

Low-temperature combustion (LTC) engines are able to reduce nitrogen oxides (NOx) and particulate matter (PM) emissions, simultaneously. LTC engines suffer from higher amounts of unburned hydrocarbon (uHC) and carbon monoxide (CO) emissions, particularly in low-load operating conditions of the engine. The existence of oxygen molecules in the alcohol fuels not only results in more combustion completeness but also leads to lower CO and uHC emissions.

The effect of tri-fuel blends on engine characteristics of a direct injection diesel engine with exhaust gas recirculation

ABSTRACT Biofuels are the most promising alternative to petro-diesel. In this work, the combined effect of mahua biodiesel and 1-Hexanol is studied on the engine characteristics. The concentration of both 1-Hexanol and mahua biodiesel is varied, 10%, 20%, and 30% each with diesel fuel. Common rail direct injection diesel engine is used in this study. Engine load is varied from 20% to 80% in step of 20%, the speed of the engine is constant throughout the experiment. Biofuel blends showed improved cylinder pressure and mean gas temperature at a higher engine load. At 60% load, 10H10M80D (10% 1-Hexanol/10% mahua biodiesel/80% diesel) showed 3.45% lower thermal efficiency and 6.11% higher fuel consumption compared to diesel. At 60% load, all the biofuel blends showed 50% lower carbon monoxide emission. At 60% load, 10H10M80D showed 33.33% lower hydrocarbon emission and 0.96% higher nitrogen oxide emission compared to baseline readings. The biofuel blends are less sensitive to exhaust gas recirculation (EGR) due to the oxygenated nature of biofuels. With 20% EGR, at 60% load, 10H10M80D showed 39.48% lower nitrogen oxide compared to no EGR. The results of 10H10M80D showed the best performance at all loads.

Comparison of efficiency and emission characteristics in a direct-injection compression ignition engine fuelled with iso-octane and methanol under low temperature combustion conditions

Gasoline and methanol are highly recommended for low temperature combustion (LTC) engines due to their high research octane number. However, engines fuelled with these fuels suffer from high unburned hydrocarbon (UHC) and carbon monoxide (CO) emissions at low loads, which can be improved by controlling the level of mixture stratification. This paper reports on the experimental and numerical comparison of the emission characteristics and engine performance of methanol and iso-octane in a heavy-duty direct-injection compression ignition engine operating in HCCI and PPC regimes. Overall, methanol requires a higher intake temperature, compared with iso-octane, to counter the high heat of vaporization. The onset of ignition is from the relatively fuel-lean regions resulting in lower CO emissions. This is due to the methanol ignition delay times being less sensitive to the fuel/air mixture and the larger temperature gradient of the equivalence ratio. Methanol achieves lower charge stratification because of its low stoichiometric A/F ratio, which extends the SOI window with ultra-low NOx emissions. However, methanol suffers from higher UHC emissions in the HCCI regime due to fuel trapped in the crevice region. Three cases include HCCI, PPC with low and high mixture stratification were detailed investigated. Of these cases, PPC with low mixture stratification case shows the highest engine thermal efficiency and the lowest emissions. Methanol has more advantages operating in the PPC regime in the aspect of emissions.

Effect of pilot fuel injection timing on the performance, combustion, and exhaust emissions of biodiesel–ethanol–diethyl ether blend fueled CRDI engine under hydrogen dual fuel strategies

AbstractThe present investigation utilizes a completely biodiesel based ternary blend pilot fuel for the hydrogen dual fuel operation in a CRDI engine. The pilot fuel was formulated with 88% biodiesel, 10% ethanol, and 2% diethyl ether to closely replicate the cetane index and heating value of petroleum diesel. The pilot injection angle was varied at 8°, 12°, 14°, 16°, and 18° before top dead center at 210 bar fuel injection pressure to study the effect of pilot fuel injection angle on performance, combustion, and emission of a hydrogen dual fuel engine at full load condition. Three different hydrogen injection durations, 1200, 2500, and 3700 μs with a constant flow rate of 0.9 kg/h were used to assess the effect of increasing hydrogen mass flow rate on the engine. The results showed that advancing pilot fuel injection angle remarkably improved the performance of engine with 13.36% higher brake thermal efficiency,9.28% lower hydrocarbon and 11.03% lower carbon monoxide emission with hydrogen injection duration of 3700 μs and pilot injection angle of 16° bTDC. However, this also increased the oxides of nitrogen emissions by 11.07%. Therefore, the results proved the efficacy of injection advancement of biodiesel based ternary blend pilot fuel in extracting better performance output from a hydrogen dual fuel CRDI engine.

The potential of oxygenated fuels (n-octanol, methylal, and dimethyl carbonate) as an alternative fuel for compression ignition engines with different load conditions

The use of oxygenated fuels can significantly reduce emissions and maintain high thermal efficiency. However, few literatures have analyzed the effects of different fuels on engine combustion and emission performances under the same oxygen content. In this study, n-octanol, methylal (ME) and dimethyl carbonate (DMC) were selected to study the effects of oxygenated fuels on the engine combustion and emissions, controlling the oxygen content of the mixture fuel about 2.5%, under the condition of 0.4 MPa−1.2 MPa. The study found that in terms of combustion performance, the introduction of n-octanol improves the heat release rate, however, the use of ME and DMC decreases the heat release rate. In addition, the use of fuel NO45 has a higher thermal efficiency than ME13, DMC8, and D100. In terms of emissions, it is concluded that NO45 has the lowest carbon monoxide emissions, followed by ME13, DMC8, and D100. The use of oxygenated fuels as NO45, ME13, and DMC8 greatly reduces the soot emissions. From the combustion and emission performances of the experimental fuels, NO45, ME13 and DMC8 can achieve a good balance between NOX and soot emissions when the loads are 0.4 MPa−1.2 MPa.

Assessing the effects of ethanol additive and driving behaviors on fuel economy, particle number, and gaseous emissions of a GDI vehicle under real driving conditions

Gasoline direct injection (GDI) vehicles operating on real roads produce particle number (PN) emissions. Ethanol, which is a vehicle oxygenated fuel, can meet stringent PN and gaseous emission regulations owing to its low carbon content, green sustainability, and clean combustion benefits. In this study, the fuel consumption (FC), PN, and gaseous emissions of a GDI vehicle were experimentally investigated using a chassis dynamometer following real driving emission (RDE). Two driving behaviors, the normal and aggressive driving modes, were tested with different ethanol fractions of gasoline (G100), 5% volume content in the blended fuel (G95E5), and 10% volume content in the blended fuel (G90E10). The results indicated that under the RDE test procedure, the FC, exhaust gas temperature (EGT), PN, carbon monoxide (CO), carbon dioxide (CO2), and nitrogen oxide (NOX) emissions in the aggressive driving mode were higher than those in the normal driving mode. When ethanol was added to gasoline, the FC and CO2 emissions of the blended fuels were higher than those of G100, whereas the CO and EGT of the blends decreased. The addition of small amounts of ethanol had little effect on the NOX emissions. As for PN, the PN emission of G95E5 was higher than that of G100. As the ethanol fraction further increased, the PN emission of G90E10 was the smallest among the three fuels. The GDI vehicles fueled with 10% ethanol achieved lower PN and CO emissions at a slight sacrifice in FC under real driving conditions.

Gaseous Emission from the Combustion of Premium Motor Spirit (PMS) from the Kaduna Refinery and Petrochemical Company (KRPC) in Nigeria

Objectives : This study characterizes the gaseous emission from the combustion of PMS of different volumes from Kaduna Refinery and Petrochemical Company.Methods : The E8500 plus combustion analyzer was used for gaseous emission characterization of different volumes. Oxygen (O2), Hydrocarbons (HC), carbon monoxide (CO), carbon dioxide (CO2), Oxides of Nitrogen NOx (NO, NO2), Sulphur dioxide (SO2), and Hydrogen Sulfide (H2S) were measured using the analyzer. The values were recorded and the descriptive statistics graph was plotted.Results and Discussion : The concentrations for the gaseous emission from the combustion of PMS were 69.85 mg/m3 HC, 117.33 mg/m3 CO, 334 mg/m3 NOx for 10 ml, 58.93 mg/m3 HC, 130.33 mg/m3 CO, 784.33 mg/m3 NOx for 20 ml, 50.20 mg/m3 HC, 84.00 mg/m3 CO, 798.67 mg/m3 NOx for 30 ml, 65.48 mg/m3 HC, 160.33 mg/m3 CO, 850.33 mg/m3 NOx for 40 ml, 87.31 mg/m3 HC, 212.67 mg/m3 CO, 801.33 mg/m3 NOx, 3.67 mg/m3 SO2 for 50 ml. This study shows that CO and HC exceeded the permissible limit for stationary sources while NOx and SO2 were below the permissible limit.Conclusions : Hence, there is a need for rapid response and urgent attention from government and regulatory bodies to develop and implement appropriate policies that will help in reducing the effect. Appropriate measures to control air emissions that may be embarked upon by regulatory bodies include increase in the use of low-emission fuels and renewable fuels such as bio-fuels and introduction of the use of devices with low CO emissions.